Sealing device



Feb. 19, 1963 c. R. STARR SEALING DEVICE Filed oct. 15, 1958 hiredStates ice 3,tl7S,1l9 SEALING DEVICE (iiiford R. Starr, Fullerton,Calif., assigner to Accessory Products Co., a division of Textron inc.,Whittier, Calif., a corporation of Rhode isiand Filed @ein 13, 1953,Ser. No. 765,819 2 Claims. (Ci. 285-336) My present invention relates tofluid type joints, and it relates more specifically to a novel sealingmeans having particu-lar utility in high pressure fluid tight joints.

Although my present invention is illustrated and hereinafter describedin connection with a joint between two sections of pipe or tubing fortransferring liquid or gas under pressure, it is to be understood thatmy novel sealing means is similarly applicable to other types of jointsbetween two elements. For example, my present sealing means may `be usedfor providing a high pressure fluid seal between a conduit and a closuremember.

Although conventional soft, flexible O-rings normally provide anadequate seal for pressures up to about two thousand p.s.i., it isusually preferable to employ metal scaling rings at higher pressures.Conventional metal sealing rings are pre-shaped to tit within the flangegrooves of the joint, and must be tightly wedged into the flange groovesin order to provide an adequate seal. The stresses are so high in jointsutilizing conventional metal sealing rings that these joints are undulybulky and heavy. Also, the tolerances are quite close in connection withthese conventional joints in order to provide an accurate seal.

In view of these and other problems in connection with conventionalprior art seals for high pressure joints, it is an object of my presentinvention to provide a novel metal sealing ring and groove constructionin which a malleable sealing ring is provided, this sealing ring havingan annular sealing edge thereon formed at the juncture between twosurfaces on the ring, this annular sealing edge being pressure moldedinto sealing engagement in a sealing groove when the two sections of thejoint are tightened together,

Another object of my present invention is to provide a novel sealingdevice of the character described which includes a malleable metalsealing ring having a generally delta cross-sectional shape, with theopposed side edges of the ring each having a pair of slightly spacedannular corners, the side edges of the ring being adapted to lit intocurved grooves in the joint with the annular corners being mashed ormolded to the shapes of the grooves when the two sections of the jointare tightened together to complete the fluid tight seal.

Another object of my present invention is to provide a novel highpressure seal of the character described which permits a substantialreduction in the size and weight of the joint embodying the seal ascompared with joints utilizing conventional prior art seals.

Other objects and advantages of my present invention Will be apparentfrom the following description and claims, the novelty of my inventionconsisting in the features of construction, the combinations of parts,the novel relations of the members, the relative proportioning,disposition and operation thereof, and the novel method steps, all as ismore completely described herein and as is more particularly pointed outin the appended claims.

In the accompanying drawings, forming a part of my presentspecification;

FlGURE l is a sectional view illustrating a sealed joint embodying thepresently preferred embodiment of my invention.

FEGURE 2 is a greatly enlarged sectional view illustrating my presentlypreferred sealing ring and groove assembly before the two sections ofthe joint have been tightened together.

FIGURE 3 is a greatly enlarged sectional View similar to FGURE 2illustrating my sealing ring and groove assembly after the ring has beencompressed in the grooves by tightening the two sections of the jointtogether.

FIGURE 4 is a sectional view similar to FIGURE 3 illustrating thealternative inward bowing of my ring as compared with the outward bowingillustrated in FIG- URE 3.

Referring to my drawings, I have illustrated a sealed joint 19 forproviding a high pressure uid tight joint between a pair of pipe ortubing sections 12 and 14.

My joint 16 includes a pair of opposed annular body portions lo and i8having respective aligned, central fluid passages 2d and 22therethrough.

The outer ends 24 and 26 of annular body portions 16 and 13 areoperatively connected to the respective pipe or tubing sections 12 andi4 by any conventional means, such as by welding.

The adjoining ends of annular body portions 16 and 18 are provided withannular anges 28 and 30 having respective mating flat annular surfaces32 and 34 disposed at right angles to the axes of annular body portions16 and 18.

The annular flanges 28 and 30 are drawn together and held with theannularsurfaces 32 and 34 seated against each other by means of aplurality of Abolts 36 disposed through a plurality of passages 37uniformly spaced around the flanges 28 and 39.

I provide opposed annular grooves 38 and 40 in the respective ilatannular surfaces 312 and 34, the grooves 33 and liti being disposedclosely adjacent to the passages 2d and 22. The grooves 38 and 4d aregenerally V-shaped, having converging outer and inner inclined groovesurfaces 42 and 44, respectively, which are joined together at curvedbottom portions 46 of the grooves 38 and 4t?.

In order to best accommodate my presently preferred delta shaped sealingring, I prefer to provide the outer groove surfaces 44 withsubstantially greater inclincs relative to the axes of the grooves thanthe inner groove surfaces 42. Although the amount of incline of thesesurfaces 42 and 44 is not in any way critical, I have found that anglesof incline relative to the axes of the grooves of about 45 for the outergroove surfaces 42 and about 15 for the inner groove surfaces 44 operatesatisfactorily.

A narrow lip 48 separates the annular groove 38 from passage Ztl, and asimilar complementary lip 50 separates the annular groove 40 frompassage 22. These lips 4S and 50 are somewhat separated to provide anannular opening 51 adapted to admit lluid under pressure from passagesZtl and 22 as hereinafter described.

My sealing ring 52 is preferably composed of a relatively soft,malleable metal which can be caused to ow under substantial pressure. Ihave found aluminum to ybe satisfactory for this purpose, although itwill be apparent that other metals can be used.

My presently preferred sealing ring 52 includes an inner cylindricalsurface S4 and generally conically inclined outer surfaces 56 and 58.The side edges 60 and 62 of sealing ring 52 preferably comprise narrowflat surfaces. The intersections of these narrow at side edges 6@ and 62with the respective outer surfaces 56 and 58 result in outer corners 64.Similarly, the intersections of these llat side edges 6d and 62 with thecylindrical inner surface 54 result in inner corners 66.

Referring now particularly to FIGURE 2 of the drawings, it will be seenthat my sealing ring 52 is somewhat wider than the combined depths ofthe two opposed grooves 38 and 4l), so that the side edges 60 and 3 62of the ring 52 will abut against the groove surfaces adjacent to thecurved bottom portions 46 of the grooves before the at annular surfaces32 and 34 of the two sections of the `joint have been drawn completelytogether.

Although the width of ring 52 relative to the combined depths of thegrooves 38 and 40` is not in any way critical, in one example where IYprovidedV an aluminum ring having an internal diameter of 1.03() inches,the ring width was .250 inch, while the combined depths of the grooveswas .230 inch. ln this same example, the radius of curvature for thecurved bottom portions 46 of the grooves was a maximum of .020 inch, andthe narrow, at surfaces of the ring side edges 60 and 62 were about .050inch wide.

After disposing the ring 52 in the position illustrated in FIGURE 2, thebolts 36 are then tightened until the flat annular surfaces 32 and 34a-re brought tightly together.

During the tightening of bolts 36, the corners 64 and 66 of ring 52 aremashed against the surfaces of the grooves 38 and 40, the corners 64 and66 owing or molding to the contours of the grooves 38 and 40 in apermanent set until the side edges of ring 52 curve generally to theshapes of the bottoms of the grooves 3x8` and 40, to provide anexcellent seal within each of the grooves 38 and 40.

It will be noted from FIGURE 3 of the drawings which illustrates thefinal sealed position of the joint that sucient compressive forces areapplied axially to the ring 52 while mashing` the slide edge corners 64and 66 in the grooves 38` and 40 to cause the entire ring 52 to bow. InFIGURE 3 of the drawings the ring 52 has bowed outwardly during thecompression. However, the direction in which the ring will bow, eitheroutwardly as in FIGURE 3, or inwardly as illustrated in FIGURE 4, willbe determined according to whether the outer corners 64 or the innercorners 66 are the lirst to engage the groove surfacesl as the twosections of the joint are drawn together. For example, if the ring isslightly on the large side, the outer corners 64 will rst engage in thegrooves, tending to bend the outer side edges 60 and 62 inwardly, aridhence tending to bow the ring in the manner shown in FIGURE 3.Alternatively, in the event the ring 52 tends to be on the small side,the inner corners 66 will rst engage the grooves, tending to bend theside edges 60 and 62 outwardly, to cause an inward Ibowing such as thatshown in FIGURE 4.

` I have found in practice that my present invention will operate justas satisfactorily regardless of whether the ring 52 bows outwardly orinwardly.k

It will be noted from the drawings that when my sealing ring 52 is inits operative sealing position as shown in FIGURES 3 and 4, there is asubstantial angle between the inner ring surface 54 and the inner groovesurfaces 44. Likewise, there is a substantial angle between the outerring surfaces 56 and 58 and the outer groove surfaces 42. Thesesubstantial angles permit the outer and inner corners 64 and 66 topresent relatively sharp edges to `the groove surfaces, whereby themashing of these edges is rendered possible without requiring undulylarge compressive forces. Accordingly, an excellent high pressure sealis set up in my present invention without requiring the usual heavy angeconstruction normally associated with high pressure seals.

In operation, uid under pressure is freely admitted from the flowpassages and 22 through the annular opening 51 so that uid pressure isapplied to the inner surface 54 of sealing ring 52. This will provide asubstantial outward force against the ring 52, giving a selfact'uatingtype of seal against the outer groove surfaces 42` which tends toimprove as the uid pressure increases.

`It will be noted that my sealing ring 52 is disposed quite close Vtothe passages 20 and 22, whereby the sealing ring 52 has the smallestpossible diameter. This results in the lowest possible forces applied bythe ring 52 against the annular body portions 16 and 18, whereby thebody portions 16 and 18 may be kept quite small in comparison withconventional high pressure joints.

By providing my ring with a delta shaped cross-section, I provideexcellent beam strength of the ring, while at the same time permittingthe side edges of the ring to be mashed into sealing engagement with thebottoms of the grooves. By orienting my delta shaped ring so that thegenerally axially directed cylindrical surface comprises the innersurface '54, I permit the ring 52 to be as closely spaced as possible tothe passages 20 and 22 through the body portions 16 and 18, to furtherminimize the forces on the body portions 16 and 18.

By mashing an annular corner edge of a malleable metal ring into sealingengagement in the groove instead of attempting to force a sealingengagement between a pre-shaped ring and a complementarily shapedgroove, I have been able to greatly reduce both the size and weight ofthe joint. For example, for comparable pressures and conduit sizes, Ihave been able to reduce the over-all weight of my sealed joint to aslittle as one-fifteenth of the weight of a conventional prior art highpressure sealed joint.

Similarly, I have been able to achieve material cost savings on theorder of nine hundred percent over the conventional high pressurejoints.

A further advantage of my present invention is that the mashing of thecorner edges of the ring into scaling engagement in the grooves providesa perfet seal regardless of minor variations in the sizes and shapes ofthe parts. Accordingly, manufacturing tolerances are not as critical inmy present invention as in conventional high pressure` joints.

It will be apparent that no permanent damage occurs to the surfaces ofthe annular grooves 38 and 40 as a result of the sealing engagement ofring 52 therein, the ring 52 being composed of substantially softermaterial than the annular body portions 16 and 18. Accordingly, if atany time it is desired for any reason to replace the sealing ring with anew ring, all that is required is to disengage the bolts 36, removingthe old ring and replacing it with a new ring, and then compressing thebody portions 16 and 18 back together in the aforesaid manner. The oldring, of course, will have a permanent bow therein, and its side edgeswill be permanently mashed.

It is to be understood that the form of my invention herein shown anddescribed is my preferred embodiment, and that various changes in theshape, size and arrange ment of parts may be resorted to withoutdeparting from the spirit of my invention or the scope of my appendedclaims.

I claim:

l. A joint including a pair of members to be sealed together against theescape of fluid under pressure, means operatively connected to saidmembers to draw and hold said members together, opposed annular groovesin said members, the walls of each groove comprising inner and outerwalls converging at an incline relative to the axis of the groove to acurved, concave groove bottom, said grooves being complementary inshape, and the outer wall of each groove being disposed at asubstantially larger angle to the axis of the groove than the innerwall, a sealing ring composed of malleable metal positioned in saidgrooves, said ring being narrower radially than said grooves at itscentral region and having narrow, flat side edges, the central region ofthe ring being thicker than the side edges, the corners of each of saidring side edges engaging against the sides of the respective groove nearthe bottom thereof, said ring having a generally delta shapedcross-section with the lat side of the delta facing the inner groovewalls and the inclined sides of the delta facing the outer groove walls,the ring being substantially wider axially than the combined depths ofsaid grooves, whereby said ring corners will be formed to the shape ofthe grooves when said ring is compressed into said grooves by drawingsaid members together.

2. A joint including a pair of members to be sealed together against theescape of iluid under pressure, means operatively connected to saidmembers to draw and hold said members together, opposed annular groovesin said members, the walls of each groove comprising inner and outerwalls converging at an incline relative to the axis of the groove to acurved, concave groove bottom, said grooves being complementary inshape, with one Wall of each groove being disposed at a substantiallylarger angle to the axis of the groove than the other Wall, a sealingring composed of malleable metal positioned in said grooves, said ringbeing narrower radially than said grooves at its central region andhaving narrow, at side edges, the central region of the ring beingthicker than the side edges, the corners of each of said ring side edgesengaging against the sides of the respective groove near the bottomthereof, said ring having a generally deltashaped cross-section with theflat side of the delta facing said other Wall of both grooves and theinclined sides of the delta facing said one Wall of both grooves, thering being substantially wider axially than the combined depths of saidgrooves, whereby said ring corners will be formed to the shape of thegrooves when said ring is compressed into said grooves by drawing saidmembers together.

References Sted in the le of this patent UNITED STATES PATENTS 392,931Prindle Nov. 13, 1888 508,765 Rouse Nov. 14, 1893 1,013,302 Messer Jan.2, 1912 2,479,612 Glidden Aug. 23, 1949 2,863,679 Dunbar Dec. 9, 1958FOREIGN PATENTS 303.408 Great Britain Dec. 28, 1928

1. A JOINT INCLUDING A PAIR OF MEMBERS TO BE SEALED TOGETHER AGAINST THEESCAPE OF FLUID UNDER PRESSURE, MEANS OPERATIVELY CONNECTED TO SAIDMEMBERS TO DRAW AND HOLD SAID MEMBERS TOGETHER, OPPOSED ANNULAR GROOVESIN SAID MEMBERS, THE WALLS OF EACH GROOVE COMPRISING INNER AND OUTERWALLS CONVERGING AT AN INCLINE RELATIVE TO THE AXIS OF THE GROOVE TO ACURVED, CONCAVE GROOVE BOTTOM, SAID GROOVES BEING COMPLEMENTARY INSHAPE, AND THE OUTER WALL OF EACH GROOVE BEING DISPOSED AT ASUBSTANTIALLY LARGER ANGLE TO THE AXIS OF THE GROOVE THAN THE INNERWALL, A SEALING RING COMPOSED OF MALLEABLE METAL POSITIONED IN SAIDGROOVES, SAID RING BEING NARROWER RADIALLY THAN SAID GROOVES AT ITSCENTRAL REGION AND HAVING NARROW, FLAT SIDE EDGES, THE CENTRAL REGION OFTHE RING BEING THICKER THAN THE SIDE EDGES, THE CORNERS OF EACH OF SAIDRING SIDE EDGES ENGAGING AGAINST THE SIDES OF THE RESPECTIVE GROOVE NEARTHE BOTTOM THEREOF, SAID RING HAVING A GENERALLY DELTASHAPEDCROSS-SECTION WITH THE FLAT SIDE OF THE DELTA FACING THE INNER GROOVEWALLS AND THE INCLINED SIDES OF THE DELTA FACING THE OUTER GROOVE WALLS,THE RING BEING SUBSTANTIALLY WIDER AXIALLY THAN THE COMBINED DEPTHS OFSAID GROOVES, WHEREBY SAID RING CORNERS WILL BE FORMED TO THE SHAPE OFTHE GROOVES WHEN SAID RING IS COMPRESSED INTO SAID GROOVES BY DRAWINGSAID MEMBERS TOGETHER.